Abstract
Lean and obese female Zucker rats were either fed ad libitum (ad libitum-fed lean and ad libitum-fed obese), food-restricted (restricted lean and restricted obese) at 50% of ad libitum intake for 3 weeks from 19-20 weeks of age, or food-restricted and then refed ad libitum for 1 week (restricted-refed lean and restricted-refed obese). Following food restriction, body weights of restricted rats were significantly lower than ad libitum-fed rats within genotype. Body weights of restricted-refed rats were not different from either ad libitum-fed or restricted rats within genotype. Restricted-refed lean rats returned to their previous ad libitum food intake, whereas restricted-refed obese rats ate significantly more food. Both restricted and restricted-refed lean rats had lowered serum insulin levels compared to ad libitum-fed lean rats, whereas there was no effect on serum insulin levels in obese rats. Liver weights and hepatocyte conversion of glucose to fatty acids, glyceride-glycerol and CO2 were not affected by food restriction or refeeding in lean rats. Among obese rats, restricted obese rats had the smallest liver weights, and restricted-refed obese rats had the highest. Restricted-refed obese rats had greater rates of hepatic glucose metabolism compared to all other groups. Ad libitum-fed lean and restricted-refed lean rats had similar fat pad weights that were significantly greater than those of restricted lean rats. Dietary intervention had no effect on fat pad weight in obese rats. There was no effect of food restriction or refeeding on adipocyte glucose metabolism except for higher glucose conversion to CO2 for restricted lean rats in comparison to values for all other groups. These results demonstrate that body weight changes of adult female obese rats in response to food restriction and refeeding are similar to those of lean rats; but the effects of liver and adipose tissue weights are different.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1029-1039 |
| Number of pages | 11 |
| Journal | Nutrition Research |
| Volume | 8 |
| Issue number | 9 |
| DOIs | |
| State | Published - Sep 1988 |
Bibliographical note
Funding Information:We thank the Obesity Research Center at St. Luke's Roosevelt Hospital Center for the glucose and insulin determinations (Core Center Grant IP30 AM 26687). This work was supported by NIH Grants AM 32965, HL 07311 and HL 08214 and by the Hormel Foundation.
Keywords
- catchup growth
- food restriction
- glucose metabolism
